Effects of NK-4 in a Transgenic Mouse Model of Alzheimer's Disease

Beta-amyloid (Aβ) peptides are considered to play a major role in the pathogenesis of Alzheimer's disease (AD) and molecules that can prevent pathways of Aβ toxicity may be potential therapeutic agents for treatment of AD. We have previously reported that NK-4, a cyanine photosensitizing dye, displays neurotrophic and antioxidant activities. In this study, we report the effects of NK-4 on the toxicity of Aβ and on cognitive function and Aβ concentration in a transgenic mouse model of AD (Tg2576). In vitro, NK-4 effectively protected neuronal cells from toxicity induced by Aβ. In addition, it displayed profound inhibitory activities on Aβ fibril formation. In vivo, Tg2576 mice received an intraperitoneal injection at 100 or 500 µg/kg of NK-4 once a day, five times a week for 9 months. Administration of NK-4 to the mice attenuated impairment of recognition memory, associative memory, and learning ability, as assessed by a novel object recognition test, a passive avoidance test, and a water maze test, respectively. NK-4 decreased the brain Aβ concentration while increasing the plasma amyloid level in a dose-dependent manner. NK-4 also improved memory impairments of ICR mice induced by direct intracerebroventricular administration of Aβ. These lines of evidence suggest that NK-4 may affect multiple pathways of amyloid pathogenesis and could be useful for treatment of AD

C-type natriuretic peptide exerts opposing effects to atrial natriuretic peptide on anxiety-related behaviour in rats.

Our present experimentation was carried out to evaluate the efficacy of hesperidin (HDN) (100mg/kg body weight), administered orally for 7 days on cyclophosphamide (CP) elicited oxidative damage on rat heart.  Cardiotoxicity inflicted by single intraperitoneal injection of CP (200mg/kg body weight) was manifested by exalted levels of CPK (creatinine phosphokinase),ALT (alanine transaminase), AST (aspartate transaminase) and LDH (lactate dehydrogenase).CP induced group depicted significant amelioration in level of MDA (malondialdehyde) , HDN treated group demonstrated inflated levels of above enzymes and decreased level of MDA.  These levels were reversed to normal levels in HDN treated group. Thus result of our study is in concordance with the notion that HDN is adept in combating myocardial free radical damage provoked by CP thus proving its protective potential